Frank Gray from Toronto races a black E30 M3. A few years ago he had a US S50 engine with ERT supercharger. The supercharger was not strong enough for racing. He then switched to a Euro engine. The job was first done by Motronix (www.motronixmotorsports.com. They could not start the engine, so the car was shipped to Raven. It took some time before they discovered they needed a European programmation to download in the DME, not the US one. It worked. The engine is reliable, it sounds stock and IT IS STOCK.